Cut the wafers into squares. Line the fat pan of the oven (32 x 39 cm) with them. Chop dark and white chocolate separately. Cut butter into pieces. Roughly chop the nuts. Melt 200 g dark chocolate and butter in a pan at low heat
Beat the eggs, brown sugar, vanilla sugar and salt in a bowl with the whisk of the hand mixer until creamy. Remove the chocolate-butter mixture from the heat and stir in. Mix flour and baking powder and fold into the chocolate mixture. Mix nuts and remaining chocolate, fold into the dough. spread the dough on the wafers and smooth it down
Bake in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for 20-25 minutes. Remove and let cool on a cake rack. Sift icing sugar and mix with 3 tablespoons of water. Spread the icing on the cooled down brownies and allow to set. Cut into pieces of approx. 6.5 x 6.5 cm
waiting time approx. 1 1/2 hours